To avoid that an outer surface of a completed automobile suffers a contamination due to soot, dusts, iron powder rust, acid rain and the like, a corrosion due to excrement of birds and insects, or a damage such as a scratch during transportation or storage of the completed automobile, it is conventionally carried out that the coated surf ace of the completed automobile is temporarily protected by a protective film formed from the strippable paint. In a technique disclosed in Japanese Patent Application Laid-open No. 6-142604, for example, a strippable paint is applied onto coated surfaces by a roller, a brush or the like along an outer peripheral edge of a region to be protected, and after or before such application, the strippable paint is sprayed to a region narrower than the region to be protected, so that an overlapped-coated zone is formed in the double-coated regions.
In the above conventional technique, however, dusts of a coating material may be spread to a wider range during spraying operation of the strippable paint, whereby the dusts may be scattered beyond the overlapped-coated zone to adhere to a portion out of the region to be protected. Therefore, a masking step is required, and/or an inspecting/correcting step is required, resulting in an increase in number of steps.
In applying the strippable paint by a roller, a brush or the like, an operation of putting the strippable paint on the roller or the brush must be repeated many times, which is troublesome. In this case, it is considered that a self-contained roller brush is used, but because a coating material supplying hose is connected to the self-contained roller brush, the direction of movement of the self-contained roller brush is limited; the weight is increased, and the operational load is increased.
The present invention has been accomplished with such circumstances in view, and it is an object of the present invention to provide a process for forming a protective film on coated surfaces of an automobile, wherein it is possible to prevent the strippable paint from being adhered to the portion out of the region to be protected, thereby simplifying the operating steps and alleviating the operational load.